f2fs: introduce __wait_one_discard_bio

In order to avoid copied codes.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index e326d8f..55064ec 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -995,6 +995,20 @@
 	mutex_unlock(&dcc->cmd_lock);
 }
 
+static void __wait_one_discard_bio(struct f2fs_sb_info *sbi,
+							struct discard_cmd *dc)
+{
+	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
+
+	wait_for_completion_io(&dc->wait);
+	mutex_lock(&dcc->cmd_lock);
+	f2fs_bug_on(sbi, dc->state != D_DONE);
+	dc->ref--;
+	if (!dc->ref)
+		__remove_discard_cmd(sbi, dc);
+	mutex_unlock(&dcc->cmd_lock);
+}
+
 static void __wait_discard_cmd(struct f2fs_sb_info *sbi, bool wait_cond)
 {
 	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
@@ -1019,13 +1033,7 @@
 	mutex_unlock(&dcc->cmd_lock);
 
 	if (need_wait) {
-		wait_for_completion_io(&dc->wait);
-		mutex_lock(&dcc->cmd_lock);
-		f2fs_bug_on(sbi, dc->state != D_DONE);
-		dc->ref--;
-		if (!dc->ref)
-			__remove_discard_cmd(sbi, dc);
-		mutex_unlock(&dcc->cmd_lock);
+		__wait_one_discard_bio(sbi, dc);
 		goto next;
 	}
 }
@@ -1049,15 +1057,8 @@
 	}
 	mutex_unlock(&dcc->cmd_lock);
 
-	if (need_wait) {
-		wait_for_completion_io(&dc->wait);
-		mutex_lock(&dcc->cmd_lock);
-		f2fs_bug_on(sbi, dc->state != D_DONE);
-		dc->ref--;
-		if (!dc->ref)
-			__remove_discard_cmd(sbi, dc);
-		mutex_unlock(&dcc->cmd_lock);
-	}
+	if (need_wait)
+		__wait_one_discard_bio(sbi, dc);
 }
 
 /* This comes from f2fs_put_super */